Annual mean 16°C · wettest around January · prevailing wind SW
Warmest
31.4 °C
Coldest
9.5 °C
Wettest
76%
Windiest
3.7 m/s
Prevailing
SW
3.0 m/s average
When this place is good five ratings · thirty-six ten-day sections · click a cell to read it
never good
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Every reading
bars actual · line feels-like, °Cchance of rain, %wind speed, m/ssky covered, %
The average temperature in Grass Valley over the whole year is 16°C. July is the hottest month, with highs of about 31°C; February is the coldest, with lows of about 5°C. The rainy (wet) season in Grass Valley runs from September to May, peaking in January with a 76% chance of rain on a given day. The dry season is June to August; July is the driest month, at 26%. Winds in Grass Valley are highest in March, averaging 2.8 m/s (10 km/h), and lightest in October, at 2.0 m/s (7 km/h). The prevailing wind is from the SW. The clearest skies in Grass Valley come in July, when the sky is typically 3% covered; March is the cloudiest month, at 43%.
Month by month Grass Valley climate by month: average temperatures year round · click a month to read it
Month
High
Low
Feels like
Chance of rain
Cloud
Wind
Being outside
Sun
Walking
January
11°C
6°C
7°C
76%
42%
2.4 m/s
7
0
53
February
12°C
5°C
8°C
75%
33%
2.6 m/s
16
0
55
March
13°C
6°C
9°C
76%
43%
2.8 m/s
20
0
59
April
17°C
9°C
14°C
72%
26%
2.7 m/s
48
5
70
May
22°C
13°C
19°C
71%
18%
2.7 m/s
65
18
63
June
28°C
18°C
25°C
44%
7%
2.6 m/s
58
49
35
July
31°C
21°C
29°C
26%
3%
2.4 m/s
38
67
14
August
30°C
20°C
28°C
35%
6%
2.3 m/s
43
68
15
September
27°C
16°C
24°C
63%
11%
2.2 m/s
61
46
37
October
22°C
12°C
19°C
70%
15%
2.0 m/s
66
20
63
November
15°C
8°C
12°C
74%
29%
2.0 m/s
30
0
71
December
11°C
5°C
8°C
76%
38%
2.1 m/s
8
0
55
High and low are the warmest and coolest of four readings a day — midnight, 6am, noon and 6pm — so a true overnight low can sit a degree or two under them. Chance of rain, cloud and wind are the day’s average; feels-like and the three ratings (each out of 100: Good from 55, Ideal from 80) are read at midday.
Seasons, and the year in short Grass Valley weather by season
Year round, Grass Valley has days of about 11°C at their warmest in January, its coolest month, and 31°C in July, its warmest; the coolest hours of the day run from 5°C to 21°C through the year, and the average temperature over the year is 16°C around the clock. Rain is most likely around January and least likely around July. Every figure here is a decade of observations blended into one representative year, so it reads as what this date is usually like, not a forecast for one particular day.
Grass Valley weather in winterDecember to February
High 11°CLow 5°CRain 75%
Winter in Grass Valley has typical daily highs of about 11°C and lows of about 5°C, with a 75% chance of rain on a given day.
Grass Valley weather in springMarch to May
High 17°CLow 9°CRain 73%
Spring in Grass Valley has typical daily highs of about 17°C and lows of about 9°C, with a 73% chance of rain on a given day.
Grass Valley weather in summerJune to August
High 30°CLow 19°CRain 35%
Summer in Grass Valley has typical daily highs of about 30°C and lows of about 19°C, with a 35% chance of rain on a given day.
Grass Valley weather in autumnSeptember to November
High 21°CLow 12°CRain 69%
Autumn in Grass Valley has typical daily highs of about 21°C and lows of about 12°C, with a 69% chance of rain on a given day.
When is the rainy season in Grass Valley?
The rainy (wet) season in Grass Valley runs from September to May, peaking in January with a 76% chance of rain on a given day. The dry season is June to August; July is the driest month, at 26%.
What time of year is Grass Valley windiest?
Winds in Grass Valley are highest in March, averaging 2.8 m/s (10 km/h), and lightest in October, at 2.0 m/s (7 km/h). The prevailing wind is from the SW.
What is the average temperature in Grass Valley year round?
The average temperature in Grass Valley over the whole year is 16°C. July is the hottest month, with highs of about 31°C; February is the coldest, with lows of about 5°C.